I would like to see the happy mask salesman again. Probably not in Skyward Sword, but in future Zelda games. Maybe we could get to know alot more about this creepy and mysterious person who always smiles.
Sheik, Saria, or Aryll. I loved Sheik because Zelda can use a few ninjas and epic poetry once and awesome jumps once in a while. Saria may not have had so much personality in the game, but the manga made her my favorite character. And Aryll because i like link having a family in the game.